Medical devices including metallic connector enclosures

ABSTRACT

Medical devices provide metallic connector enclosures. The metallic connector enclosures may be constructed with relatively thin walls in comparison to polymer connector enclosures to aid in miniaturizing the medical device. The metallic connector enclosures may be constructed with interior surfaces that deviate less from an ideal inner surface shape in comparison to polymer connector enclosures to allow for better concentricity of electrical connectors. The metallic connector enclosures may include a panel that allows access to the cavity of the connector enclosure where set screw blocks, lead connectors, spacers, seals, and the like may be located. Furthermore, the lead connectors within the metallic connector enclosures may be separated from the metallic connector enclosure by being positioned within non-conductive seals that reside within features included in cavity walls of the connector enclosure. Similarly, set screw blocks may be separated from the metallic connector enclosure by non-conductive spacers present within the cavity.

TECHNICAL FIELD

Embodiments relate to medical devices that have connector enclosuresthat receive medical leads. More particularly, embodiments relate tomedical devices that have metallic connector enclosures.

BACKGROUND

Medical devices including those that may be implanted and those that areworn externally on the body of the patient utilize medical leads tocarry signals between circuitry within the medical device and electrodeson distal ends of the medical leads. The medical leads may be used todeliver electrical stimulation pulses from the medical circuitry to thetissue and/or to sense physiological signals from the tissue and conveythose signals to the medical circuitry.

Typically, the medical lead is a separate item from the medical device.The lead is routed within the body of the patient to the area wherestimulation or sensing is to occur. A proximal end of the lead isconnected to the medical device by inserting the lead into a connectorenclosure of the medical device. The connector enclosure establisheselectrical contact between electrical connectors on the lead andcorresponding lead connectors within the connector enclosure. Theconnector enclosure may provide seals that engage the medical lead andprevent body fluids from entering into the connector enclosure of themedical device.

The connector enclosure of the medical device is often a polymer whichis formed over the lead connectors and lead frames that provide aconductor from the electrical connector to electrical contacts on thebase of the connector enclosure. The medical device also includes ahermetically sealed can that is typically constructed of a metal such astitanium. The can has feedthrough pins exiting a top of the can that areattached to the electrical contacts of the connector enclosure duringassembly of the medical device to complete the electrical pathways fromthe medical circuitry to the lead connectors of the connector enclosure.

The polymer connector enclosure may have various drawbacks. Forinstance, the polymer connector enclosure typically requires asignificant volume to provide adequate strength. The polymer wallthicknesses are necessarily large enough to adequately support the leadconnectors and lead frames present within the connector enclosure, whichmay inhibit the ability to further miniaturize the medical device.Furthermore, the inner surfaces of the connector enclosure that engagethe lead connectors have a relatively large deviation from an idealinner surface shape. These deviations cause the longitudinal sequence oflead connectors to have relatively large variations in concentricity,which leads to a relatively large lead insertion force and thatcontributes to lead damage during insertion.

SUMMARY

Embodiments address issues such as these and others by provide a medicaldevice that has a metallic connector enclosure. The inherent strength ofthe metal allows the connector enclosure to be made with relatively thinwalls to aid in miniaturization of the medical device. Furthermore, theprecision that is achievable when creating the inner surfaces of theconnector enclosure such as by machining allows the deviation from anideal shape to be relatively small to better align components so as toaid in reducing insertion force. To allow access to the interior of theconnector enclosure for assembly purposes, a cavity may be created withan open area that can be covered by a panel that is bonded in place.Furthermore, to isolate lead connectors from the metallic connectorenclosure, non-conductive lead connector spacers may be included withinthe cavity of the metallic connector enclosure.

Embodiments provide a method of constructing a medical device. Themethod involves providing a can that houses medical circuitry andproviding electrical connectors within the can and electricallyconnected to the medical circuitry. The method further involvesproviding a metallic connector enclosure comprising a metallic bodydefining a cavity and a metallic panel welded to the metallic body andcovering the cavity, the body including an opening to the cavity. Themethod involves providing lead connectors within the cavity and inalignment with the opening, the lead connectors being positioned betweenthe metallic body and the metallic panel and providing electricalconductors that are electrically connected to the lead connectors withinthe cavity and that are electrically isolated from the metallicconnector enclosure while being exposed outside of the metallicconnector enclosure. The method involves placing a portion of the can incontact with a metallic edge of the metallic connector enclosure suchthat the electrical connectors within the can and the electricalconductors exposed outside the metallic connector enclosure are incontact and are contained by a housing created by the contact of the canand the metallic connector enclosure and creating a bond at the contactof the portion of the can and the metallic edge of the metallicconnector enclosure.

Embodiments provide a method of constructing a medical device. Themethod involves providing a can that houses medical circuitry andproviding electrical connectors within the can and electricallyconnected to the medical circuitry. The method further involvesproviding a metallic connector enclosure defining a cavity and includingan opening to the cavity, the metallic connector enclosure includingwalls with portions of at least one wall having a thickness of 25thousandths of an inch or less. The method involves providing leadconnectors within the cavity and in alignment with the opening andproviding electrical conductors that are electrically connected to thelead connectors within the cavity and that are electrically isolatedfrom the metallic connector enclosure while being exposed outside of themetallic connector enclosure. The method involves placing a portion ofthe can in contact with a metallic edge of the metallic connectorenclosure such that the electrical connectors within the can and theelectrical conductors exposed outside the metallic connector enclosureare in contact and are contained by a housing created by the contact ofthe can and the metallic connector enclosure and creating a bond at thecontact of the portion of the can and the metallic edge of the metallicconnector enclosure.

Embodiments provide a method of constructing a medical device. Themethod involves providing a can that houses medical circuitry andproviding electrical connectors within the can and electricallyconnected to the medical circuitry. The method further involvesproviding a metallic connector enclosure having internal walls defininga cavity with the metallic connector enclosure including an opening tothe cavity. The method further involves providing a plurality of leadconnectors within the cavity and in alignment with the opening, each ofthe lead connectors being surrounded by a seal, each of the sealsseparating the lead connectors from the internal walls where acenterline of each lead connector varies by 8 thousandths of an inch orless from the centerline of every other lead connector. The methodinvolves providing electrical conductors that are electrically connectedto the lead connectors within the cavity and that are electricallyisolated from the metallic connector enclosure while being exposedoutside of the metallic connector enclosure. The method involves placinga portion of the can in contact with a metallic edge of the metallicconnector enclosure such that the electrical connectors within the canand the electrical conductors exposed outside the metallic connectorenclosure are in contact and are contained by a housing created by thecontact of the can and the metallic connector enclosure and creating abond at the contact of the portion of the can and the metallic edge ofthe metallic connector enclosure.

Embodiments provide a method of constructing a medical device. Themethod involves providing a can that houses medical circuitry andproviding electrical connectors within the can and electricallyconnected to the medical circuitry. The method further involvesproviding a metallic connector enclosure comprising a metallic bodydefining a cavity, the body including an opening to the cavity, thecavity having a recess and providing non-conductive lead connectorspacers within the recess. The method further involves providing leadconnectors within the cavity and in alignment with the opening, the leadconnectors being disposed within the non-conductive lead connectorspacers and providing electrical conductors that are electricallyconnected to the lead connectors within the cavity and that areelectrically isolated from the metallic connector enclosure while beingexposed outside of the metallic connector enclosure. The method involvesplacing a portion of the can in contact with a metallic edge of themetallic connector enclosure such that the electrical connectors withinthe can and the electrical conductors exposed outside the metallicconnector enclosure are in contact and are contained by a housingcreated by the contact of the can and the metallic connector enclosureand creating a bond at the contact of the portion of the can and themetallic edge of the metallic connector enclosure.

Embodiments provide a medical device that includes a can that housesmedical circuitry and electrical connectors within the can andelectrically connected to the medical circuitry. The medical deviceincludes a metallic connector enclosure comprising a metallic bodydefining a cavity and a metallic panel welded to the metallic body andcovering the cavity, the body including an opening to the cavity. Themedical device includes lead connectors within the cavity and inalignment with the opening, the lead the connectors being positionedbetween the metallic body and the metallic panel, and includeselectrical conductors that are electrically connected to the leadconnectors within the cavity and that are electrically isolated from themetallic connector enclosure while being exposed outside of the metallicconnector enclosure. A portion of the can is in contact with a metallicedge of the metallic connector enclosure such that the electricalconnectors within the can and the electrical conductors exposed outsidethe metallic connector enclosure are in contact and are contained by ahousing created by the contact of the can and the metallic connectorenclosure, and a bond is present at the contact of the portion of thecan and the metallic edge of the metallic connector enclosure.

Embodiments provide a medical device that includes a can that housesmedical circuitry and electrical connectors within the can andelectrically connected to the medical circuitry. The medical deviceincludes a metallic connector enclosure defining a cavity and includingan opening to the cavity, the metallic connector enclosure includingwalls with portions of at least one wall having a thickness of 25thousandths of an inch or less. The medical device includes leadconnectors within the cavity and in alignment with the opening andelectrical conductors that are electrically connected to the leadconnectors within the cavity and that are electrically isolated from themetallic connector enclosure while being exposed outside of the metallicconnector enclosure. A portion of the can is in contact with a metallicedge of the metallic connector enclosure such that the electricalconnectors within the can and the electrical conductors exposed outsidethe metallic connector enclosure are in contact and are contained by ahousing created by the contact of the can and the metallic connectorenclosure, and a bond is present at the contact of the portion of thecan and the metallic edge of the metallic connector enclosure.

Embodiments provide a medical device that includes a can that housesmedical circuitry and electrical connectors within the can andelectrically connected to the medical circuitry. The medical devicefurther includes a metallic connector enclosure having internal wallsdefining a cavity with the metallic connector enclosure including anopening to the cavity. The medical device further includes a pluralityof lead connectors within the cavity and in alignment with the opening,each of the lead connectors being surrounded by a seal, each of theseals separating the lead connectors from the internal walls where acenterline of each lead connector varies by 8 thousandths of an inch orless from the centerline of every other lead connector. The medicaldevice includes electrical conductors that are electrically connected tothe lead connectors within the cavity and that are electrically isolatedfrom the metallic connector enclosure while being exposed outside of themetallic connector enclosure. A portion of the can is in contact with ametallic edge of the metallic connector enclosure such that theelectrical connectors within the can and the electrical conductorsexposed outside the metallic connector enclosure are in contact and arecontained by a housing created by the contact of the can and themetallic connector enclosure, and a bond is present at the contact ofthe portion of the can and the metallic edge of the metallic connectorenclosure.

Embodiments provide a medical device that includes a can that housesmedical circuitry and an electrical connector within the can andelectrically connected to the medical circuitry. The medical deviceincludes a metallic connector enclosure comprising a metallic bodydefining a cavity, the body including an opening to the cavity, thecavity having a recess and a non-conductive lead connector spacer withinthe recess. The medical device includes a lead connector within thecavity and in alignment with the opening, the lead connector beingdisposed within the non-conductive lead connector seal and an electricalconductor that is electrically connected to the lead connector withinthe cavity and that is electrically isolated from the metallic connectorenclosure while being exposed outside of the metallic connectorenclosure. A portion of the can is in contact with a metallic edge ofthe metallic connector enclosure such that the electrical connectorwithin the can and the electrical conductor exposed outside the metallicconnector enclosure are in contact and are contained by a housingcreated by the contact of the can and the metallic connector enclosure,and a bond is present at the contact of the portion of the can and themetallic edge of the metallic connector enclosure.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a front perspective view of a medical system includes amedical device example according to various embodiments and a medicallead.

FIG. 2 shows a rear perspective view of the medical device example.

FIG. 3 shows a rear view of the medical device example with a rearportion of a can and a rear panel removed.

FIG. 4 shows a rear view of the medical device example with an isolationcup removed.

FIG. 5 shows a front view of the medical device example with the canremoved.

FIG. 6 shows a bottom perspective view of a connector enclosure exampleof the medical device with the panel removed.

FIG. 7 shows a top perspective view of the connector enclosure exampleof the medical device with an antenna support cover removed.

FIG. 8 shows a rear view of the connector enclosure example of themedical device with set screw blocks and a set screw spacer, a frontseal, and an antenna support removed.

FIG. 9 shows a rear perspective view of the connector enclosure of themedical device with lead connectors, spacers, and feedthrough pinsremoved.

FIG. 10 shows an interior side of the panel of the connector enclosure.

FIG. 11 shows a perspective view of a base of the connector enclosure.

DETAILED DESCRIPTION

Embodiments provide for medical devices that have a can housing medicalcircuitry and have a connector enclosure with a metallic weld to thecan. In one or more embodiments, the metallic weld provides a relativelystrong attachment between the connector enclosure and the can even wheremedical adhesive is not used to aid in attaching the connector enclosureto the can. In one or more embodiments the metallic weld provides ahermetic seal for the can. Furthermore, in one or more embodiments, theconnector enclosure may have a relatively small size such as where thecan omits barbs, pins, straps, and other features ordinarily used toattach a connector enclosure to a can.

FIG. 1 shows an example of a medical system 100 that includes anembodiment of a medical device 102 and a corresponding medical lead 104.The medical device 102 includes a can 106 that houses medical circuitryand also includes a connector enclosure 108 that is attached to the can106 and houses the electrical connections to the lead 104. The connectorenclosure 108 includes one or more openings 114 that receive theproximal end of the medical lead 104. The connector enclosure 108 ofthis particular example includes a connector enclosure body 112 wherethe openings 114 are located and a connector enclosure base 110 uponwhich the connector enclosure body 112 is mounted. An antenna cover 116that may be constructed of materials such as polysulfone or polyurethaneis mounted atop the connector enclosure 108 as the antenna cover 116resides atop the connector enclosure body 112.

As shown in FIG. 2, the connector enclosure 108 may also includeadditional features. Far instance, a connector enclosure panel 118covers a cavity within the connector enclosure body 112 which isdiscussed in more detail below. In this particular example, the panel118 includes an outwardly protruding region 132 that accommodates itemslocated within the cavity being covered by the panel 118. Also in thisexample, a seal 120 that is constructed of a material such as liquidsilicone rubber or a medical adhesive creates a seal between the screwblock and grommet covered set screws 122 are present.

A set screw block discussed below is present within the set screw blockspacer, also discussed below, that underlies the seal 120 where theopenings 114 lead to passages in the set screw block. The lead 104passes through the passages in the set screw block, and a clink 126 ofthe lead 104 resides within the set screw blocks upon full insertion ofthe lead 104. The set screw 122 is tightened against the clink 126 tosecure the lead 104 within the connector enclosure 108. Thus, the setscrew block within the spacer 180 may also act as a lead connector.Conventional seals may be present within the openings 114 to sealagainst the clink 126 and resist the entry of bodily fluids into theopenings 114.

The medical lead 104 includes a lead body 128 typically constructed of apolymer followed by the metal clink 126 and then an alternating seriesof non-conductive spacers 130 typically constructed of a polymer andelectrical connectors 124 that are typically metal. The electricalconnectors 124 and in some examples the clink 126 are connected toelectrical conductors within the lead body 128 that extend to a distalend where electrodes are present at the stimulation/sensing site. Uponinsertion of the lead 104 into the connector enclosure 108, theelectrical connectors 124 align with lead connectors that areelectrically connected to the medical circuitry within the can 106.

In the example shown in FIGS. 1-11, it may be desirable that theconnector enclosure 108 be bonded to the can 106 by a metallic weld. Inthat case, at least a top edge of the can 106 is a metal such as variousgrades of titanium while at least a bottom edge of the connectorenclosure 108 is also a metal such as various grades of titanium. In theexample shown, the entire can 106 is a metal such as grade 5 titaniumwhile at least the connector enclosure base 110 of the connectorenclosure 108 is also entirely a metal such as grade 5 titanium.

As shown in FIGS. 3 and 4, wherein a rear half of the can 106 is removedfor purposes of illustration while a front half 136 of the can 106remains, the connector enclosure base 110 of this example includes alower edge 166 of a lip that the upper edge of the can 106 residesagainst. Accordingly, the metallic weld, such as a laser seam weld, maybe performed along the lower edge 166 of the lip to create the bondbetween the connector enclosure base 110 and the can 106. Forembodiments where the bond is other than a metallic weld, such as whereconventional mounting techniques and medical adhesives are used instead,the upper edge of the can 106 and/or the lower edge of the connectorenclosure 108 may be materials other than metal.

The can 106 of this example also includes an open top. The connectorenclosure base 110 mates to the open top with the top edge of the opentop of the can 106 meeting the lower edge 166 of the lip on theconnector enclosure base 110. Thus, the connector enclosure base 110acts as a lid to close the open top of the can 106, and upon beingmetallically welded together, creates a hermetically sealed enclosure.

The panel 118 may be metallic as may be the connector enclosure body112. Thus, where the connector enclosure base 110 is also metallic,particularly for embodiments where the connector enclosure 108 is bondedby a metallic weld to the can 106, the entire connector enclosure 108may be metallic. For instance, the connector enclosure body 112 may be agrade 5 titanium while the panel 118 may be a grade 1 titanium that isstamped rather than machined, or a grade 5 titanium that is alsomachined. An entirely metallic connector enclosure 108 may be relativelystrong while being small and with relatively precise features asdiscussed in more detail below.

Where the connector enclosure 108 includes a metal connector enclosurebase 110, a metal connector enclosure body 112, and a metal connectorenclosure panel 118, each of these pieces may be welded together tocomplete the enclosure. The bonds between the body 112, the base 110,and/or the panel 118 may alternatively be other than metallic weldsparticularly for embodiments where the body 112, the base 110, or thepanel 118 is other than a metal. For instance, the bond between the bodyand the base 110 may utilize medical adhesive barbs, straps, and thelike for embodiments where one or both of the base 110 and body 112 arenot metal.

The panel 118 is removed for purposes of illustration in FIGS. 3 and 4,where the connector enclosure body 112 of this particular exampleincludes a slight indention 168 within which the panel 118 rests. Thus,the panel 118 may be bonded to the body 112 by a metallic weld such as alaser seam weld along the edge of the indention 168. Similar to thealternative bonds between the base 110 and the body 112, alternativemanners of joining the panel 118 to the body 112 may also be used, suchas medical adhesive barbs, straps, and the like, especially forembodiments where one or both of the panel 118 and body 112 are notmetal.

During assembly of the connector enclosure 108, the panel 118 may beleft aside while components are installed into the cavity within theconnector enclosure body 112. These components may include the setscrewblock spacer 180, a set of lead connectors 146, lead connector seals 148disposed between the lead connectors 146, and end seals 142. Feedthroughpins 144 which are electrical conductors that carry individualelectrical signals between the interior of the can 106 and the interiorof the connector enclosure 108 may also be positioned within the cavityand bonded to the lead connectors 146 such as by a resistance weld orother weld.

The feedthrough pins 144 exit the connector enclosure 108 viafeedthrough passageways 200 within the connector enclosure base 110 asshown in FIG. 10. These feedthrough passageways 200 may provide a sealagainst the feedthrough pins 144, as show in FIG. 6, by includingferrules 178 that the feedthrough pins 144 pass through that are filledwith a glass or other non-conductor 176 that creates a seal and alsogives the feedthrough pins a fixed position relative to the base 110.This seal to the feedthrough pins 144 allows the can 106 to achieve thehermetic seal upon the connector enclosure base 110 being mounted andbonded to the can 106.

As shown in FIGS. 4 and 5, the exposed tip 156 of the feedthrough pins44 are bonded to electrical contacts 158 of a flexible circuit connector170 which is shown transparently for purposes of illustration. Theflexible circuit connector 170 extends down to meet electricalconnections of medical circuitry 152. The medical circuitry 152 mayinclude such items as a microcontroller device, a memory device,stimulation capacitor, a telemetry device, a battery 141, and the like.

As shown in FIG. 3, the medical circuitry 152 is contained within anisolation cup 138 that is constructed of a material such as a liquidcrystal polymer, polypropylene, and the like and that is removed forpurposes of illustration in FIGS. 4 and 5. The isolation cup 138 fitswithin the can 106 and may have a physical connection to the connectorenclosure base 110. For instance, in some embodiments the connectorenclosure base 110 may include feet 140 as shown in FIG. 5, and theisolation cup 138 may have an interference or snap fit to the feet 140.A desiccant may also be present within the can 106 such as within apocket of the isolation cup 138, while a rubber bumper 172 or bumper ofother similar material may be present within the can 106 below theisolation cup 138 so that the isolation cup 138 comes to rest in a fixedand supported position within the can 106.

As shown in FIGS. 4 and 5, a coil assembly 154 may be included togetherwith the medical circuitry 152 within the isolation cup 138. This coilassembly 154 may be used for various purposes. For instance, the coilassembly 154 may be used to receive recharge energy and/or provide nearfield telemetry. The coil assembly 154 may include a coil housing thatis constructed of a material such as a liquid crystal polymer,polypropylene, and the like with the coil wound within the housing.

The coil assembly 154 and the frequency at which the coil assembly 154operates are less affected by surrounding metal than the telemetryantenna so the coil assembly 154 is included within the can 106 of thisembodiment. The telemetry antenna is positioned atop the connectorenclosure 108 where it is not surrounded by metal, as discussed furtherbelow in relation to FIG. 7. Consequently, in this particularembodiment, the coil assembly 154 and the telemetry antenna arephysically separated from one another. However, it will be appreciatedthat where the coil assembly 154 and the telemetry antenna operate infrequency bands that are significantly spaced from one another, thephysical separation between the two is less a factor when using bothsimultaneously.

In the particular example shown in FIG. 4, the connector enclosure base110 provides an integrated filtered feedthrough utilizing monolithiccapacitors. One or more filter plates 150 are attached to the undersideof the connector enclosure base 110 such as by medical adhesive,soldering, and the like. In this example, the filter plates 150 areconstructed of ceramic with wire traces present within the ceramic thatestablish electrical continuity with the feedthrough pins 144 while alsoestablishing capacitance within the conductive path of the traces. Thewire traces of the filter plates 150 are electrically coupled to theconnector enclosure base 110 by soldering of the edges of the filterplates 150 for embodiments where the connector enclosure base 110 ismetal to effectively ground the feedthrough capacitors to the base 110,as well as to the can 106 for embodiments where the connector enclosurebase 110 is welded or otherwise conductively attached to the can 106.

As can be seen in FIG. 6, the connector enclosure base 110 of thisexample includes a recessed area 174 which provides a location forinstallation of the filter plates 150. FIG. 6 and FIG. 4 also show aground pin 160 that is present within the connector enclosure base 110.This ground pin 160 also electrically connects to the flexible circuitconnector 170 to provide a ground connection for the medical circuitry152. The ground pin 160 is then welded or otherwise bonded to theconnector enclosure base 110 for embodiments where the connectorenclosure base 110 is a metal to thereby establish the ground with thebody of the patient and the metallic portions of the can 106.

Additionally, for embodiments where a telemetry antenna 183 as seen inFIG. 7 is provided atop the connector enclosure 108, an antenna pin 162may be included that passes through the connector enclosure base 110 andconnects to the flexible circuit connector 170. As shown in FIG. 6, theantenna pin 162 may be isolated from the base 110 via a ferrule filledwith a glass or other non-conductor as with the other feedthrough pins144. However, the antenna pin 162 is not filtered by the filter plates150 so that the telemetry signals are not subject to attenuation fromthe capacitive filters of the filter plates 150. A connecting portion164 of the antenna 183 as shown FIGS. 4 and 7 may then connect theantenna pin 162 to the antenna conductor present within the 183 cover116. The connecting portion 164 may be an integral section of theconductor forming the telemetry antenna 183 as shown in FIG. 7 or may bea separate conductor bridging the telemetry antenna 183 to the antennapin 162.

The connector enclosure base 110 may include features to aid in theconstruction of the medical device 102. For instance, the connectorenclosure base 110 may provide the feet 140 that extend into theisolation cup 138 to provide a snug fit of the isolation cup 138 to theconnector enclosure base 110 prior to the connector enclosure base 110being bonded to the can 106. Additionally, in this example where thetelemetry antenna 183 is positioned atop the connector enclosure 108,the connector enclosure base 110 includes a slot 134 that receives afoot of the antenna cover 116 to aid in holding the antenna cover 116and the antenna 183 within the antenna cover 116 in place.

FIG. 7 provides a view of the feedthrough pins 144 passing through thefeedthrough passageways 200 that include the ferrules 178 from a topperspective. Here, it can be seen that the lead connectors 146 arepositioned in longitudinal alignment with corresponding feedthroughpassageways 200 of the enclosure base 110. This longitudinal alignmentallows the feedthrough pins 144 to be straight in the longitudinaldimension which facilitates assembly and reduces feedthrough pin length.The feedthrough pins 144 of this example have bends in the transversedimension which allows the feedthrough pins 144 to mount to the leadconnectors 146 at the outer sides while returning to a more centrallocation where the feedthrough passageways 200 are located. Thisconfiguration aids in assembling the stacked configuration of lead boresas shown.

In this particular example, the lead connectors 146 for a top leadpassageway are offset in the longitudinal direction relative to the leadconnectors 146 for a bottom lead passageway. This allows the feedthroughpins 144 for the lead connectors 146 of the top lead passageway to passby the non-conductive lead connector seals 148 for the lead connectors146 of the bottom lead passageway. In this manner, the feedthrough pins144 of the top lead passageway do not interfere with the lead connectors146 or feedthrough pins 144 of the bottom lead passageway. Furthermore,the feedthrough pins 144 are spaced from the walls of the cavity formedin the connector enclosure body 112 which may be metal so that theelectrical signals are not short circuited to ground and are notattenuated to a degree that might affect operation of the medical device102.

FIG. 7 also provides a view of the cavity within the connector enclosure108 where the set screw block spacer 180 is removed for purposes ofillustration to reveal a recess 186 of the cavity that is machined orotherwise manufactured to have inner surfaces that accommodate andsecure the set screw block spacer 180. This spacer 180 may beconstructed of a non-conductive rigid material such as polysulfone whichmay directly contact metal walls of the cavity within the connectorenclosure body 112 while supporting the set screw blocks and isolatingthe set screw blocks from the metal walls so that electrical signals arenot short circuited to ground and are not attenuated to a degree thatmight affect operation of the medical device 102. Other machined orotherwise manufactured inner surface features are discussed furtherbelow with reference to FIG. 9.

To ensure that the seal 120 will properly adhere to the set screw blockspacer 180, the set screw block spacer 180 may be manufactured such asby applying a coating of siloxane. The siloxane layer may then beprimerized with a layer of silicone medical adhesive which may bediluted with a heptanes solvent. The seal 120 may then be applied atopthe medical adhesive primer layer, such as by applying liquid siliconerubber to form the seal 120.

FIG. 7 also shows an antenna support 184 that the antenna conductor 183may rest upon or be encased by, and the antenna support 184 lies withinthe antenna cover 116 which has also been removed for purposes ofillustration. In this particular example, the connector enclosure body112 includes an arced top upon which the antenna cover 116 rests. Theantenna support 184, which may be constructed of materials such aspolysulfone, polyurethane, and the like, isolates the antenna conductor183 from the connector enclosure body 112, which is particularly ofinterest for embodiments that include a metallic connector enclosurebody 112. The antenna support 184 may be coated in the same mannerdiscussed above for the set screw block spacer 180 so that portions ofthe antenna support 184 that extend into the cavity of the cavity of theconnector enclosure body 112 may adhere to the liquid silicone rubberthat has been inserted into the cavity of the connector enclosure body112.

The antenna cover 116 and/or the antenna support 184 may provide asealed passageway for the connecting pin 164 to pass from the portion ofthe cavity behind the end seal 142 to the interior of the antennasupport 184 where contact with the antenna conductor 183 is made. Theantenna support 184 includes suture holes 187 which align with sutureholes that may also be included in the antenna cover 116 that allow themedical device 102 to be sutured in place within the body of thepatient.

The connector enclosure base 110 of this example includes a lip with anupper edge 182. The panel 118 rests at the upper edge 182 of the lipwhere a laser seam weld may be created to attach the bottom edge of thepanel 118 to the upper edge 182 of the lip. As discussed above, thetower edge 166 of the lip on the connector enclosure base 110 restsagainst an upper edge of the can 106 where a laser seam weld may becreated to attach the connector enclosure base 110 to the can 106.

In FIG. 8, the antenna support 184 is removed for purposes ofillustration. The outer surface 185 of the connector enclosure body 112where the antenna cover 116 rests can be seen. The antenna cover 116includes longitudinal ribs that slide into longitudinal grooves 189formed into the top of the connector enclosure body 112. These grooves189 hold the antenna cover 116, and hence the antenna support 184, in afixed position relative to the connector enclosure body 112. Theconnector enclosure base 110 may be subsequently moved into positionrelative to the connector enclosure body 112 which involves placing theend of the antenna cover 116 into the slot 134 in the connectorenclosure base 110. The slot 134 runs orthogonally to the grooves 189such that the antenna cover 116 and antenna support 184 are locked inplace on the connector enclosure 108.

FIG. 9 shows the connector enclosure body 112 mounted to the connectorenclosure base 110 but with all other components removed for purposes ofillustration. The features of the interior walls within the cavity ofthe enclosure body 112 are in view. Considering that the connectorenclosure body 112 and the interior walls of the cavity in particularmay be constructed of metal, the features of the interior walls may bemachined or otherwise manufactured to include a variety of features toaccommodate the components that reside within the connector enclosure108.

In this example, additional recesses 190 that accommodate, align, andsecure the lead connectors 146 and lead connector seals 148 can be seen.The recesses 190 align with the openings 114 to provide longitudinalpassageways where the lead connectors 146 and lead connector seals 148are present as shown in the preceding figures to ultimately receive theleads 104.

As shown in FIG. 8, the lead connector seals 148, which may beconstructed of non-conductive materials such as liquid silicone rubber,urethane, and the like, operate as spacers to both separate the leadconnectors 146 from the interior walls of the cavity formed in theconnector enclosure body 112 and to separate one lead connector 146 froman adjacent lead connector. In one particular example, the leadconnectors 146 may be canted coil spring connectors such as thoseavailable from the Bal Seal Engineering company.

The seals 148 may create various nearest edge to nearest edge spacingbetween the connectors 146, for instance from 16 thousandths of an inchfor some embodiments to 33 thousandths of an inch for others.Furthermore, the seals 148 may create various spacing between the cavitywalls and the nearest edge of the connectors 146, for instance from 10thousandths of an inch for some embodiments to 15 thousandths of an inchfor others. The non-conductive seals 148 effectively isolate theelectrical connectors 146 from the metal walls and adjacent electricalconnectors 146 so that electrical signals are not shorted to ground andare not attenuated to a degree that affects operation of the medicaldevice 102.

The alignment of the lead connector seals 148 and the lead connectors146 directly impact the amount of insertion force necessary to insert alead 104. The proximal end of the lead 104 passes through each leadconnector 146 until the lead 104 is fully inserted into the connectorenclosure 108. As the proximal end of the lead 104 approaches the fullyinserted position, all lead connectors 146 of a given lead passagewayare engaging the lead body and/or connectors 124. Each lead connector146 thereby causes friction with the lead 104 during insertion whichresults in a given insertion force. The less the concentricity from onelead connector 146 to the next varies, the smaller the amount ofinsertion force required to insert the lead. A smaller amount ofinsertion force has a smaller likelihood of damaging the medical lead104.

In the example shown in FIG. 9, the lead passageway recesses 190 areformed by machining or other precision method such that the centerlineof each lead connector 146 in the longitudinal direction varies by 8thousandths of an inch or less from the centerline of every other leadconnector 146 in some embodiments, for instance 4 thousandths of an inchor less for embodiments with walls constructed of various grades oftitanium or similar metals. For instance, the connector enclosure body112 may be titanium and the recesses 190 may be machined into thetitanium to provide this degree of concentricity for the lead connectors146.

A recess 188 that accommodates and secures the end seal 142 can also beseen in FIG. 9. In this example, the end seal 142 shown in FIG. 8 is adouble seal that captures the most proximal lead connector 146 for boththe upper and the lower lead passageways. It will be appreciated thatindividual end seals could be used in place of a double seal for twolead passageways, such as where multiple recesses 188 may be present toaccommodate and secure each end seal or where a single recess 188 asshown accommodates two individual end seals in a stacked configuration.The end seal 142, which may also be constructed of a non-conductivematerial such as a liquid silicone rubber, urethane, and the like,effectively isolates the final electrical connectors 146 from the metalwalls so that electrical signals are not shorted to ground and are notattenuated to a degree that affects operation of the medical device 102.

In this example shown in FIG. 9, the connector enclosure body 112 alsoincludes a set of recesses 192 that align with feedthrough passageways200 in the connector enclosure base 110. These recesses allow thefeedthrough pins 114 of that side of the connector enclosure body 112 topass into the feedthrough passageways 200 without obstruction whileretaining a robust lower support for the lead connector seals 148 of thelower lead passageway.

Where the connector enclosure body 112 is constructed of a material thatis relatively sturdy, such as titanium or other biocompatible metals,the walls of the enclosure body 112 may be made relatively thin whichallows for an overall reduction in the volume of the connector enclosure108. For instance, in this example where the connector enclosure body112 is constructed of a metal such as titanium, the walls for therecesses 186 and 188 are the thinnest walls for the enclosure body 112and may be machined or otherwise formed so that the thickness is on theorder of 25 thousandths of an inch or less in some embodiments, such as8 thousandths of an inch for various grades of titanium and similarmetals. Other embodiments may provide for the thinnest walls to be inother locations within the cavity in addition to or as an alternative tothe recesses 186 and 188 having the thinnest walls.

In this embodiment where the telemetry antenna 183 sits atop theconnector enclosure 112, the connecting pin 164 passes through a sealthat is mounted within an opening 194 present within the connectorenclosure body 112 to enter the antenna support 184. The antenna cover116 may have the seal integrally formed so that upon mounting theantenna cover 116, the seal is disposed within the opening 194. In thisparticular example, the antenna pin 162 extends from the feedthroughpassageway of the connector enclosure base 110 into a region between theend seal 142 and the opening 194, as shown in FIG. 8. With the opening194 on the end of the connector enclosure 108 opposite the leadpassageway openings 114, the conduction path from the antenna pin 162 tothe antenna 183 within the housing 184 avoids intersections with otherfeedthrough pins 144, lead connectors 146, set screw blocks, and theleads 104 themselves.

FIG. 10 shows the inner side of the connector enclosure panel 118. Thepanel 118 includes a peripheral surface that rests against the indention168 of the connector enclosure body 112 once the panel 118 is bonded inplace by a laser seam weld or other bond. The panel 118 of thisembodiment includes the region 132 that is concave when viewed on theinner side as shown in FIG. 10. This region 132 accommodates the seals148 and lead connectors 146 forming the lead passageways as well as thefeedthrough pins 144 present between the seals 148 and the panel 118.This concavity allows the width of the connector enclosure body 112 tobe less than the width needed for clearance in the region 132 to therebyreduce the overall volume of the connector enclosure 108.

The panel 118 also includes an opening 196 where the set screw block isexposed to insert the set screws and set screw grommets 122 into the setscrew block and where the seal 120 can be added to seal the junction ofthe opening 196 and grommets to the set screw spacer and set screwblock. The opening 196 of this embodiment is also present within aconcavity that allows the connector enclosure body 112 to have a widththat is less than the width needed for clearance of the set screw blockspacer 180 to further reduce the overall volume of the connectorenclosure 108.

Where the panel 118 is welded to the connector enclosure body 112, thepanel 118 may be constructed of various biocompatible metals. Forinstance the panel 118 may be constructed of various grades of titaniumsuch as grades 1 or 5. However, constructing the panel 118 of a grade 1titanium allows the panel to be stamped more easily although the panel118 may be manufactured in other ways such as by machining. Thethickness of the panel 118 may be relatively small, similar to thethinnest walls of the connector enclosure base 112, because of theinherent strength in a metal panel 118. The panel 118 may have athickness on the order of 25 thousandths of an inch or less for someembodiments that use metal, such as 8 to 12 thousandths of an inch forvarious grades of titanium and similar metals.

FIG. 11 shows an example of the connector enclosure base 110 with otherelements of the connector enclosure 108 removed. In this example, theconnector enclosure base 110 includes an upper edge 198 of the lip wherethe connector enclosure body 112 may be seated and ultimately welded inplace. The connector enclosure base 110 provides the feedthroughpassageways 200 and also provides a ground pin passageway 202. Theground pin 160 terminates within the ground pin passageway 202 where itis welded to the connector enclosure base 110.

The connector enclosure base 110 may be constructed of variousmaterials. For embodiments where the connector enclosure base 110 iswelded to the top edge of the can 106 and/or welded to the connectorenclosure body 112, the connector enclosure base 110 is constructed of abiocompatible metal. For instance, the connector enclosure base 110 maybe constructed of grade 5 titanium that is machined to provide thefeatures as shown.

One manner of assembling the example of the connector enclosure 108shown in FIGS. 1-11 may proceed as follows. The connector enclosure base110, feedthrough pins 144, filter plates 150, ground pin 160, andantenna pin 162 may be pieced together and bonded physically andelectrically as appropriate. The lead connectors 146, seals 148, and endseal 142 may be pieced together and placed into the recesses 188 and 190of the connector enclosure body 112. The set screw block spacer 180containing the set screw blocks may be placed into the recess 186 withthe feedthrough pins 144 corresponding to the set screw blocks beingwelded to the set screw blocks while the seals for the openings 114 maybe inserted.

Prior to bringing the connector enclosure body 112 together with theconnector enclosure base 110, the antenna cover 116 including theantenna support 184 the antenna conductor 183, and the antennaconnecting pin 164 are pieced together an joined to the connectorenclosure body 112. As discussed above, in this example the antennacover 116 slides onto the grooves 189 of the connector enclosure body112 while the connecting pin 164 and related portion of the antennacover 116 pass into the opening 194 of the connector enclosure body 112.

The connector enclosure base 110 is then mounted to the connectorenclosure body 112 by sliding the connector enclosure base 110transversely into position relative to the body 112 and then bonded thetwo such as by a metallic weld. In doing so, the feedthrough pins 144move into contact with corresponding feedthrough plate passages whilebeing accommodated by the recesses 192. Likewise, the antenna pin 162moves into contact with the connecting pin 164 while the bottom of theantenna cover 116 slides into the slot 134 of the connector enclosurebase 110. The feedthrough pins 144 may then be welded to the leadconnectors 146 while the antenna pill 162 may be welded to theconnecting pin 164.

The components within the cavity of the connector enclosure body 112 arecomplete. The panel 118 is then placed over the cavity and welded intoplace within the indention 168 of the connector enclosure body 112 whichholds the end seal 142 and the set screw block spacer 180 into place andthereby assists in holding the lead connectors 146 and seals 148 inplace within the cavity. The panel 118 is bonded to the connectorenclosure body 112 and connector enclosure base 110, such as by ametallic weld to complete the assembly of the connector enclosure 108. Afiller material such as liquid silicone rubber is injected within thecavity of the connector enclosure body 112 through a remainingpassageway to fill the cavity and the passageway. The grommets may beinstalled and the seal 120 is poured into place.

One manner of assembling the medical device 102 may proceed as follows.The connector enclosure 108 is assembled as discussed above. The medicalcircuitry 152, coil assembly 154, battery 141, flexible circuitconnector 170, and bumper 172 are pieced together and the exposed ends156 of the feedthrough pins 144, ground pin 160, and antenna pin 162 arebonded to conductive pads 158 on the flexible circuit connector 170. Theisolation cup 138 is then placed around the medical circuitry 152, coilassembly 154, battery 141 and flexible circuit connector 170, with theisolation cup 138 being fitted to the feet 140 of the connectorenclosure base 110.

The isolation cup 138 and those items within the isolation cup 138 aredeposited into the top opening of the can 106. The isolation cup 138 andthose items within the isolation cup 138 slide down into the can 106until the bumper 172 contacts the bottom interior wall of the can 106.At that time, the top edge of the can 106 engages the lower edge 166 ofthe lip around the connector enclosure base 110. The top edge of the can106 is then bonded at the point of contact to the connector enclosurebase 110 such as by a metallic weld to complete the assembly of themedical device 102.

While embodiments have been particularly shown and described, it will beunderstood by those skilled in the art that various other changes in theform and details may be made therein without departing from the spiritand scope of the invention.

What is claimed is:
 1. A method of constructing a medical device,comprising: providing a can that houses medical circuitry; providingelectrical connectors within the can and electrically connected to themedical circuitry; providing a connector enclosure that includes atleast one metallic wall, an opening to a cavity, and a base having aplurality of feedthrough pin passageways spaced longitudinally;providing lead connectors within the cavity and aligned with theopening, the lead connectors being spaced longitudinally in alignmentwith the feedthrough pin passageways; providing a plurality offeedthrough pins that are electrically connected to the lead connectorsand that pass through the feedthrough pin passageways in a fixedrelationship relative to the base to extend externally of the connectorenclosure; placing a portion of the can in contact with the base of theconnector enclosure such that the electrical connectors within the canand the feedthrough pins externally of the base are in contact and arecontained by a housing created by the contact of the can and theconnector enclosure; and creating a bond between the contact of theportion of the can and the base of the connector enclosure.
 2. Themethod of claim 1, wherein the can has an opening defined by an edge andwhere creating the bond is done so that the base covers the opening. 3.The method of claim 1, wherein the connector enclosure comprises a bodythat defines the cavity, includes the at least one metallic wall, and isfully metallic.
 4. The method of claim 1, further comprising providingat least one feedthrough filter plate bonded to the base, thefeedthrough filter plate including a plurality of feedthrough pinpassageways that receive the feedthrough pins, the feedthrough filterplate including conductors that are capacitively coupled to thefeedthrough pins.
 5. The method of claim 1, wherein the base comprises ametal.
 6. The method of claim 1, wherein the connector enclosure furthercomprises a titanium panel that covers the cavity.
 7. The method ofclaim 1, wherein the base is metallic and the bond is a metallic weld.8. A method of constructing a medical device, comprising: providing acan that houses medical circuitry; providing electrical connectorswithin the can and electrically connected to the medical circuitry;providing a connector enclosure that includes at least one metallicwall, an opening to a cavity, and a base having a plurality offeedthrough pin passageways; providing lead connectors within the cavityand aligned with the opening; providing a plurality of feedthrough pinsthat are electrically connected to the lead connectors and that passthrough the feedthrough pin passageways in a fixed relationship relativeto the base to extend externally of the connector enclosure; providingat least one feedthrough filter plate bonded to the base, thefeedthrough filter plate including a plurality of feedthrough pinpassageways that receive the feedthrough pins, the feedthrough filterplate including conductors that are capacitively coupled to thefeedthrough pins; placing a portion of the can in contact with the baseof the connector enclosure such that the electrical connectors withinthe can and the feedthrough pins externally of the base are in contactand are contained by a housing created by the contact of the can and theconnector enclosure and such that the conductors of the feedthroughfilter plate are electrically coupled to the can; and creating a bondbetween the contact of the portion of the can and the base of theconnector enclosure.
 9. The method of claim 8, wherein the can has anopening defined by an edge and where creating the bond is done so thatthe base covers the opening.
 10. The method of claim 8, wherein the canis fully metallic.
 11. The method of claim 8, wherein the connectorenclosure comprises a body that defines the cavity, includes the atleast one metallic wall, and is fully metallic.
 12. The method of claim8, wherein the base comprises a metal.
 13. The method of claim 8,wherein the connector enclosure further comprises a titanium panel thatcovers the cavity.
 14. The method of claim 8, wherein the base ismetallic and the bond is a metallic weld.
 15. A method of constructing amedical device, comprising: providing a can that houses medicalcircuitry; providing electrical connectors within the can andelectrically connected to the medical circuitry; providing a connectorenclosure that includes at least one metallic wall, an opening to acavity wherein at least a portion of the cavity is defined by the atleast one metallic wall, the connector enclosure further including abase having a plurality of feedthrough pin passageways; providing leadconnectors within the cavity and aligned with the opening, a count oflead connectors that are present within the cavity being equal to acount of feedthrough pin passageways that are present within the base;providing a plurality of feedthrough pins that are electricallyconnected to the lead connectors and that pass through the feedthroughpin passageways in a fixed relationship relative to the base to extendexternally of the connector enclosure; placing a portion of the can incontact with the base of the connector enclosure such that theelectrical connectors within the can and the feedthrough pins externallyof the base are in contact and are contained by a housing created by thecontact of the can and the connector enclosure; and creating a bondbetween the contact of the portion of the can and the base of theconnector enclosure.
 16. The method of claim 15, wherein the can has anopening defined by an edge and where creating the bond is done so thatthe base covers the opening.
 17. The method of claim 15, wherein theconnector enclosure comprises a body that defines the cavity, includesthe at least one metallic wall, and is fully metallic.
 18. The method ofclaim 15, further comprising providing at least one feedthrough filterplate bonded to the base, the feedthrough filter plate including aplurality of feedthrough pin passageways that receive the feedthroughpins, the feedthrough filter plate including conductors that arecapacitively coupled to the feedthrough pins.
 19. The method of claim15, wherein the base comprises a metal.
 20. The method of claim 15,wherein the base and can are fully metallic and the bond is a metallicweld.